Fungi of Arkansas-OLD PAGE
Members of the kingdom Fungi, or Mycetae, are an integral part of our biosphere. The history of mankind contains many examples of human-fungal interactions that sometimes affected large populations of humans, and perhaps changed the course of human events. For example, mass hysteria and a “mob mentality” historically have been used to explain the Salem witch trials, but more recent evaluation has pointed to the possibility of a fungal cause. Rye was used to make bread, and grains of rye can be tainted by ergot, which is caused by the fungus Claviceps purpurea. Consumption of ergot creates symptoms (ergotism) such as muscle spasms and convulsions, hallucinations, delusions, unclear speech, and a sense of crawling skin. Those symptoms were present in the “witches” of Salem, and it has been argued that rye tainted by the fungus produced the symptoms leading to the witch trials. Even further, ergot has been implicated as a factor contributing to repressed immune systems and a higher mortality rate during the times of the plagues in Europe.
Another famous example of human history being affected by outbreaks of fungus is the potato blight in Ireland that forced many inhabitants to leave their country of origin. A large part of the human population of Ireland depended on potatoes as the staple food, but when the blight appeared, caused by the fungus Phytophthora infestans, an estimated 20-25% of the population was lost to starvation or emigration.
Early in human history, people learned of the beneficial uses of particular kinds of fungi, such as the ability of yeasts to convert sugars into ethanol. Knowledge of other benefits from cultivating fungi came later – the use of certain molds to flavor cheese and the discovery that some molds produced chemicals that are toxic to certain pathogenic strains of bacteria. The ecological discovery that the penicillin mold (Penicillium sp.) produced a chemical that inhibited growth of bacteria contributed to the study and development of antibiotic medications.
Also, humans learned that certain fungi such as truffles and morels were very delectable and succulent, and thus desirable as exotic foods. The desirability and variety of edible mushrooms and fungi has only increased over time. Consumers now have access to mushrooms that were hand-picked from the forests, as well as to a larger selection of cultivated fungi that were grown on woody substrates. Many of these culinary morsels were not available several years ago.
David Hawksworth, a renowned mycologist, conservatively estimated that the global diversity of fungi would include about 1.5 million species (Hawksworth, 1991). This estimate was based on a 6:1 ratio of fungi to vascular plants in temperate climates, and an estimate of 270,000 vascular plants occurring worldwide. Due to the wide confidence margins used in formulating the 1990 estimate, coupled with the knowledge that fungal diversity in the tropics is greater than that in temperate regions, Dr. Hawksworth (2001) noted that his original estimate was perhaps too low and should be revised in the near future.
Within the total number of globally-known species of mushrooms and related fungi, the following groups contain these numbers of species: Agaricales (fleshy fungi with the traditional mushroom shape, i.e. cap and stem) - 80,000, Gasteromycetes, (puffballs, stink horns) - 10,000, Aphyllophorales, (chanterelles, toothed fungi, and polypores) - 20,000, and the jelly fungi, which include the orders Tremellales, Auriculariales, and Dacrymycetales - 5,000. Thus, the total number of known species of mushrooms and allied fungi worldwide numbers about 115,000 (Hawksworth, 2001).
Of this worldwide value of 115,000, 8,000 to 10,000 species occur in North America. With different climates and rainfall patterns, it should not come as a surprise that different areas of the country have different kinds of mushrooms and fungi.
What is the difference between a mushroom and a fungus? All mushrooms are fungi, but not all fungi are mushrooms. “Fungi” refers to a kingdom of living organisms that encompasses rusts, molds, and yeasts, as well as those entities that we call mushrooms. In most field guides, the term mushroom usually is applied to those fleshy fungi that either (1) have the traditional morphology of a mushroom, i.e., a cap with gills underneath and a stem, or (2) do not have this traditional appearance but are edible, i.e., puffballs and morels.
Many of the species of mushrooms and other higher fungi (also known as macrofungi) collected in the eastern and southern regions of the United States are native to Arkansas. Thus, descriptions of eastern species found in popular national-level field guides (Lincoff, 1981; McKnight and McKnight, 1987; Phillips, 2005) can be helpful in identifying mushrooms found in our state. In addition, many of the mushrooms depicted in regional field guides for the South (Weber and Smith, 1985), the Southeastern United States (Bessette et al., 2007) and Texas (Metzler and Metzler, 1992) also be found in Arkansas. Following is a look at the different kinds of macrofungi that can be found in Arkansas, organized into three groups on the basis of how they obtain their nutrients.
Types of Fungi
Parasitic FungiSpring Fungi
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